Live Blog: Floyd Mayweather versus Marcos Maidana

Welcome to SI.com's live blog of the Floyd Mayweather-Marcos Maidana fight. Here's your primer for the fight, including background, undercard, and programming notes.

6:35 PM Welcome to SI.com's live coverage of Floyd Mayweather's welterweight showdown against Marcos Maidana. The Blog is ringside at the MGM Grand Garden Arena in Las Vegas and will be bringing you round by round coverage tonight. Keep this page bookmarked and check back in around 11 ET/8 PT.

9:03 Welcome back to the MGM Grand, where we are just minutes away from Mayweather-Maidana. A few thoughts on the undercard

- Undefeated super middleweight contender J'Leon Love won a unanimous decision over Marco Antonio Periban in a surprisingly entertaining fight. Periban was active early, even dropping Love in the fifth round. Love, who was very well conditioned, took control in the later rounds, bloodying Periban with a crisp jab and potent power shots.

- In an equally unentertaining bout, junior welterweight contender Adrien Broner battered Carlos Molina to win a lopsided decision. Broner--coming off a loss to Maidana last December--was carefully matched against Molina, a journeyman coming off a 17-month layoff. Molina landed a few decent shots early before Broner took control, popping Molina with combinations and disfiguring his face. It was an easy fight--and a fat $1.25 million payday--for Broner. Broner now has a decision to make: Stay at 140-pounds or move back to 147. Either way, the polarizing Broner will be in a big fight.

-In the co-main event, Amir Khan dropped Luis Collazo three times in a blowout decision win. Collazo tried to rough Khan up, moving in with his hands down trying to goad Khan into a brawl. But Khan fought a better tactical fight than we have seen in the past. He moved well around the ring and didn't engage in the type of slugfest we have seen in the past. Showtime was hoping for a spectacular Khan win to build some momentum towards a fall fight with Floyd Mayweather, should Mayweather win later tonight. Khan wasn't spectacular, but the win was decisive.

9:12 Some housekeeping before the fighters are introduced. Maidana, who weighed in at 146.5 pounds on Friday, rehydrated to 165-pounds. Mayweather, who weighed in at 146-pounds, added just two pounds to 148. Final odds, according to the MGM Grand, made Mayweather a favorite at around 8-1.

9:15 Maidana on his way to the ring. Warm--though far from deafening--reaction for the WBA welterweight champion

9:17 Mayweather headed to the ring. He is led by a circus act. Literally, a circus act. Jugglers. Tumblers. And, of course, Justin Bieber

9:23 Here we go...

ROUND 1: Mayweather moves right to the middle of the ring to meet Maidana. Paws at Maidana with the jab. Mayweather tags Maidana with a two-punch combination. Maidana mucks it up on the inside. Referee warns Maidana for grabbing the head. Maidana landed a few shots in there. Maidana swinging wildly now! Hits Mayweather with a few, Mayweather blocks the rest. Chopping shots from Maidana. Mayweather backed into the ropes. A shot to the back of the head by Maidana. Mayweather responds with hard combinations. A short hook definitely hurt Maidana. Great round. Give it to Maidana 10-9 Maidana

ROUND 2: Mayweather again showing brilliant patience. He is waiting for Maidana to create openings and tagging him. Short hook lands on Maidana. Maidana again makes it rough against the ropes. Hard straight right by Mayweather. They are trading punches against the ropes. Mayweather goes back to the jab. Taps Maidana to the body. Maidana looking a lot less aggressive. Hard straight right by Mayweather just before the bell. 10-9 Mayweather

ROUND 3: Maidana again pushes Mayweather towards the ropes. Mayweather sticks with the jab, Maidana wings an overhand right. Mayweather goes back to the body. He loves that soft jab to the belly. Good combination by Mayweather. Another combination by Mayweather. Maidana fouls Mayweather after the referee calls stop. Referee warns Maidana. Nice uppercut by Maidana lands against the ropes. More chopping rights by Maidana. He's dropping his head and firing away. Close round. Could go either way. Give it to Floyd. 10-9 Mayweather

ROUND 4: Maidana continues to come forward. Lot of grabbing and holding. Maidana complains that Mayweather is using his elbows too much. Hard shot by Maidana to the body. Good clean body shot by Floyd. Crowd chanting Chino Chino now. Nice body attack by Maidana. Mayweather looks like he is cut over his right eye. Pawing at it. Blinking to get the blood out. Maidana finishes the round with a nice attack against the ropes. 10-9 Maidana

ROUND 5: Mayweather smiles at Maidana as he comes out of the corner. Definitely cut over the right eye. Nice counter right by Mayweather. Mayweather much more elusive in this round. Word is the cut is being ruled an accidental head butt. Good overhand right by Maidana. Chopping shot that landed. Mayweather back to the jab. The actions slows a little. Maidana charges in during the final ten seconds. Slower round, but give it to Maidana. 10-9 Maidana

ROUND 6: Mayweather just doesn't look as sharp as usual. Credit Maidana. He is making this a street fight. Judging could be very interesting in this fight. Maidana pushes Mayweather to the corner again. Mayweather lands a good body shot. Back to back lefts by Mayweather land clean. Maidana felt those. Good right by Mayweather hurt Maidana. And again! Maidana pushes Mayweather back to the ropes. Hard left hand by Mayweather. Another before the bell. Clear round for Mayweather. 10-9 Mayweather

ROUND 7: Mayweather starting to get it going. Responds to a Maidana push with two crisp shots. Taps Maidana with a hook. Mayweather bangs away at Maidana's body against the ropes. Maidana throws a few chopping overhand shots. Maidana back to the body. Mayweather pivots out of the corner, lands again. Whenever Mayweather is against the ropes, he ducks away from all of Maidana's hard shots. Maidana looks a little tired. Breathing through his mouth. Good round for Mayweather. 10-9 Mayweather

ROUND 8: Maidana digging at Mayweather's body. Smacks Floyd with a low blow. No call from the referee. Mayweather taps Maidana more to the body. Maidana flicking the jab a little more. Not a lot of clean action in this round. But give it to Maidana, who appeared to land a few more punches. 10-9 Maidana

ROUND 9: Maidana wings a right hand that misses Floyd's body. Straight right by Floyd lands flush on Maidana's jaw. Good counter shot by Maidana. Nice combination to the head and body by Mayweather. Mayweather just a step faster than Maidana. Another good combination by Mayweather. Maidana continues to push Mayweather against the rips. Two straight combinations by Mayweather. Maidana paws with the jab now. Now it's Mayweather pushing Maidana back. Maidana looked a little stung by one of those body shots. Give another round to Mayweather 10-9 Mayweather

ROUND 10: Floyd continues to be more assertive in these later rounds. Maidana having a hard time finding him against the ropes. Maidana chops at Mayweather's body during a clench. Hard right by Floyd. Some ugly action in this round. Maidana still pressuring but these shots are being blocked. Mayweather cracks Maidana with a good shot to the body. Another. Hard right by Mayweather to Maidana's head. Another right by Mayweather at the bell. 10-9 Mayweather

ROUND 11: Mayweather's conditioning is excellent, as usual. His combinations continue to land. A jab bounces off Maidana's head. Mayweather continues moving well, continues to pot shot Maidana. Not sure how much Maidana has left in the tank. Good flurry by Maidana against the ropes. Nice overhand right by Maidana. Two nice short lefts by Mayweather. The two get tangled up and tumble halfway through the ropes! Both up. Close round. I lean towards Mayweather. 10-9 Mayweather

ROUND 12: Crowd on its feet. Two good lefts by Mayweather slip Maidana's guard. Mayweather slips a rush by Maidana and tags him with a combinations. Maidana bullies Mayweather back into the corner. Both fighters get caught in the ropes. Mayweather is so good defensively. Never drops that guard. Maidana is a bull in a china shop. Hard right by Mayweather lands. Good counter right by Floyd. He's going to win this round. 10-9 Mayweather

10:14 Close fight. Good fight. SI.com scores it 116-112 for Mayweather. Let's go to the judges...